Planet Formation Timescale and Accretion Rate of Onc

The purpose of this study is to learn about the lifetime of inner disc to find the timescale of the planet formation and to find the accretion rate of ONC to understand the extent to which mass accretion rate influence the protostars in ONC. To find the disc lifetime, IR excess values are found first in the wavelengths J, H, K bands and 3.6, 4.5, 5.8, 8 and 24 micrometer lines and then the spectral energy distribution (SED) is plotted. The slope of SED helps in classifying the stars which also helps to understand the nature of the disc. The relation of slope with mass and age is obtained to find the variation in disc fraction with mass and age. Then the change in disc fraction with age is found from the exponential relation, which tells the evolutionary pattern of the discs. From this exponential relation the lifetime of disc can be obtained. One of the methods in which disc can lose its particle is by mass accretion. Hence, the mass accretion rate is found and then the extent to which the accretion rate has influenced the sources in ONC were also found.